2006 Ulysses, Micron full race system, fitted eight years ago, Kuryakyn Hypercharger recently fitted, new battery and TPS reset done, this week. Bike fires up and ticks over at a steady 1000RPM. Move off and the bike splutters and coughs through 2000RPM and clears at 3000RPM. From 3-6000RPM runs fantastic.Rear Cylinder exhaust gas hotter than front cylinder and the slight sign of pale blue smoke from rear cylinder but it clears quickly. 20000 miles on the engine. Where do I start looking?

Checked exhaust system (Micron built in four parts) no exhaust leaks. TPS reset done with Texas Instruments all on a laptop. ECM Spyware requires physical alteration of the injector butterfly. Has the TPS been carried out correctly?

Since you are in troubleshooting mode, try removing the Hypercharger and going back to whatever bits were there before the modification, and see if the problem goes away. If it does, the Hypercharger is the problem.

It could be that at certain RPM ranges,or more accurately certain airflow velocities through the intake tract, there is a 'harmonic' with the Hypercharger that is affecting engine performance.

Over the coming days I will remove the Hypercharger and reinstall the K+n. However, the bike was running reasonably well in March when I completed the modifications. This 2000 RPM problem has crept in this month and is getting more disruptive, harder to ride around.

Fuel injectors sonically cleaned and tested, all good. Fuel pump removed and full of crap so new fuel pump installed. Better but not perfect. next week I will get a TPS done and hopefully that will be it. How do you know if the TPS sensor is not working?

TPS is a linear potentiometer. Potentiometer's have a wiper inside them that moves along a variable resistor, changing the resistance that is then sent to the ECM.

TPS can be tested with ECMspy. Or you can get a multimeter with mini-clip ends and attach to the TPS leads. Rotate the throttle from full closed to full open and you should see a linear resistance change without any "dead" spots.